Category: Swarm

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Dike intrusion in Askja volcano

Today (14.12.2012) around 12:00 UTC Askja volcano had dike intrusion. This dike intrusion was not in the main volcano it self. But a good distance away from it. But this is in a area that has erupted before in distant past in a fissure style eruption (just lava, no volcano ash). What is the case now I am not sure at the moment. But this dike intrusion was at the depth of 25 to 22 km. So it has long way to go before any eruption takes place. This dike intrusion did also not show any sign of moving upwards according to Rúv News of this event.


Earthquake map from IMO showing the dike intrusion clearly. Copyright of this image belongs to Icelandic Meteorological Office.

What this means in the long term is impossible to know at this point. But this is one event in a long series of events that started in March 2010. This is going to end with a eruption. Large or small is impossible to know until it happens. What is also impossible to know is when and where such eruption might take place. As is always the case with active volcanoes. There is at least no reason to panic about this. Not now, not ever.

Donations: I am still needing donations to cover my cost of buying 3G hardware for upcoming geophone stations Böðvarshólar (total cost around 1300 DKK, or 29900 ISK). I have got some donations already. But they just cover the cost of UPS and USB card for Skeiðflöt geophone station. But I was fixing technical problems with it. Thanks for the support.

Icelandic News about this

Á annan tug skjálfta austur af Öskju (Rúv.is)

Blog post updated at 23:29 UTC on 14.12.2012

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Interesting earthquake swarm in TFZ

Today (12.12.2012) there was a interesting earthquake swarm in south part of TFZ (close to a place called Ásbyrgi). This earthquake swarm did consist mostly of minor earthquakes. With magnitudes of from ML0.2 and up to magnitude ML2.6. This earthquake swarm is tectonic in nature. I do not believe it is volcanic in nature. But this earthquake swarm is inside Krafla volcano fissure swarm or TFZ-NVZ two volcanoes. I am not sure in this case here.


The earthquake swarm is in the corner of this image. Copyright of this image belongs to Icelandic Meteorological Office.

This earthquake swarm might not mean anything special as is. But earthquake activity in this area has been some for the past few years. But it has so far never resulted in any major events so far in this area.

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TFZ earthquake swarm update on 06.12.2012

The earthquake swarm on TFZ continues to this day. It has been ongoing for more then one month already. The largest earthquake in the past few days has been a earthquake with the magnitude of ML2.7. Most other earthquakes that have been taking place are in the magnitude range of ML0.0 and up to ML2.7. Activity in this area happens with high and lows. With latest high being just few days ago. This continued earthquake activity shows that this area continues to be at risk of large earthquake.


Earthquake activity in TFZ yesterday (05.12.2012). It continues in the same area as Mb5.6 earthquake that took place on 21. October 2012. Copyright of this image belongs to Icelandic Meteorological Office.


Earthquake activity in TFZ today (06.12.2012). Not many new earthquake have taken place since yesterday (05.12.2012. Picture above). But there is regular activity in this area and that makes the earthquake swarm continuous. Copyright of this image belongs to Icelandic Meteorological Office.

Currently there are no signs that this earthquake swarm is about to end. Even if there is a drop in activity for a day or two. It continues as it has been doing since 21st October 2012. I am going to post updates on this earthquake swarm regularly. If anything major happens. I am going to post update soon as I can do so.

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Earthquake activity update on 16.11.2012

Here is a short update on earthquake activity in Iceland. It has been stormy few weeks so recorded earthquake activity has not been a lot in Iceland.

Tjörnes Fracture Zone

Earthquake activity continues in TFZ. A bit less then when it did start on 20. October 2012. But it still moves along. The risk of large earthquake area remains for this area. When, where and how big remains unknown factors so far.


Earthquake activity in TFZ. Copyright of this image belongs to Icelandic Meteorological Office.

Herðubreiðarfjöll volcano

Herðubreiðarfjöll volcano is a small volcano (no GVP entry that I know of) just north of Askja volcano. But Herðubreiðarfjöll volcano are in fact part of Askja volcano fissure swarm. But I do not think they are part of Askja volcano as such.


Earthquake activity in Herðarbreiðarfjöll volcano (the blue dots). Copyright of this image belongs to Icelandic Meteorological Office.

The earthquake activity in Herðurbreiðarfjöll volcano was most likely a minor dike intrusion into the volcano. What that means is too early to say at this moment. But most likely it does not mean anything for now at least.

There has been some minor ice-quake activity in Iceland when the temperature drops below 0 degrees in Iceland.

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Renewed earthquake activity in TFZ

Earthquake activity has renewed at TFZ. The area that is activate is the same area that had earthquake swarm from about 1 month ago. But largest earthquake in that swarm was a Mb5.6 earthquake. The largest earthquake today was a magnitude ML3.3 earthquake at 12:12 UTC. A magnitude 2.8 earthquake did take place at 13:08 UTC.


Current earthquake activity in TFZ. Green star mark the magnitude magnitude ML3.3 earthquake. Copyright of this image belongs to Iceland Meteorological Office.

The risk of large earthquake in this area still high. When it might happen is impossible to know for sure. There have been reports of the largest earthquake being felt in the town of Siglufjörður and other nearby areas. I fully expect earthquake activity to continue in this area. There have been stormy conditions in Iceland for the past 24 hours. This winter storm is making it more difficult to detect smaller earthquakes in this area, as in other areas of Iceland.

This earthquake activity appears clearly on my geophone in Hvammstangi. Even if there is a lot of wind noise taking place.

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Earthquake swarm in TFZ continues, little earthquake activity in Katla voclano, new earthquake activity in Askja volcano

Here is a short update on activity in Iceland for the past few days.

Tjörnes Fracture Zone

Earthquake activity continues in Tjörnes Fracture Zone. But this earthquake activity has been ongoing since 20 October, 2012. Every once in a while a magnitude 3.0 earthquake takes place, or larger. The risk of large earthquake taking place in this area remains. General alert for this area is also in effect because of this danger of large earthquake taking place in this area.


The earthquake activity in TFZ. Copyright of this image belongs to Icelandic Meteorological Office.

Katla volcano

Winter has come. At least when it comes to earthquake activity in Katla volcano. But little to none earthquake activity is now taking place in Katla volcano. Earthquake activity is now well below background level. It can be expected that current status is going to remain in Katla volcano until next summer.


Earthquake activity in Katla volcano for the past few days. Nothing important is taking place in Katla volcano as this image clearly shows. Copyright of this image belongs to Icelandic Meteorological Office.

Askja volcano

While Katla volcano is getting quiet. It seems that Askja volcano is getting slightly more active. But earthquake activity in Askja volcano during the past few weeks suggests a minor magma intrusion (dike intrusion) might have taken place. But none of the earthquakes that took place where above magnitude 2.0 in size.


Earthquakes in Askja volcano during the past few days. Copyright of this image belongs to Icelandic Meteorological Office.

I do not think this earthquake activity in Askja volcano means it is getting close for an eruption. Since there are no signs in that direction at the moment. But this earthquake activity is interesting. What ever it means in the short term for Askja volcano. It is also common that volcanoes have earthquake activity without anything happening at all following such earthquake activity.

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Earthquake activity update for Iceland and TFZ

This is update for TFZ over the past few days. Along with update for earthquake activity in Iceland during the past few days.

Tjörnes Fracture Zone

Earthquake swarm in TFZ continues. In the past days the largest earthquakes have had the magnitude of ML3.2. A second earthquake swarm is also taking place west of the village of Kópasker. That area also had an earthquake with the magnitude of ML3.2. That earthquake swarm is unrelated to the earthquake swarm taking place off north of Siglufjörður village. Earlier today an earthquake with the magnitude 3.8 took place. More earthquakes are expected to take place. This latest earthquake was clearly felt in Siglufjörður village. This earthquake swarm started on 20th of October. So it has been ongoing now for almost two weeks.


The latest earthquake in TFZ. Copyright of this image belongs to Icelandic Meteorological Office.


Earthquake tracker from Icelandic Meteorological Office showing the earthquakes during the past 48 hours in TFZ. Copyright of this image belongs to Icelandic Meteorological Office.

Earthquake activity is expected to continue in this part of TFZ. The risk of large earthquake in this area has not yet passed. Most of the earthquakes appears clearly on my geophone in Hvammstangi.

Iceland activity

Other the earthquake activity in TFZ. It has been generally quiet in Iceland. For the past four days there has been really bad winter storm taking place in Iceland. With wind up to 40m/s and wind gust up to 70m/s or more. This means that fewer earthquakes are being detected by the SIL network in Iceland due to increased wind noise. But earthquake activity has been low in Iceland for the past few weeks (besides TFZ). So I am not sure if that changes anything. There is no volcano activity taking place in Iceland at the moment.

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TFZ earthquake swarm ongoing after 10 days

The earthquake swarm that started in TFZ on 20.10.2012 continues. It has slowed down a little bit. But is still making earthquakes with the magnitude above 3.0 every few hours to days as it currently stands. This earthquake swarm at current time does not show any signs of stopping. Uncertainty level is in effect for north part of Iceland at the moment.


The earthquake activity from the start in this area of TFZ. Copyright of this image belongs to Icelandic Meteorological Office.


Current activity in TFZ. Copyright of this image belongs to Icelandic Meteorological Office.

It is hard to know for sure what happens next in this earthquake swarm. But I am sure it is going to continue as is. But as I sad above. This earthquake swarm does not show any signs of stopping for now. This earthquake swarm does not drop the risk of a large earthquake in this area of Iceland. At least while it is ongoing. Regardless of what happens later.

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TFZ earthquake swarm update on 26.10.2012 at 16:12 UTC

The earthquake activity in TFZ continues today, as it has done so for the past six days. Yesterday there was little change in earthquake activity in TFZ. General alert for the risk of earthquake larger then Mw6.0 is still in place and is going to remain in place for at least few more days.


The earthquake activity in TFZ on 26.10.2012. Copyright of this image belongs to Icelandic Meteorological Office.

It is impossible to know for sure what happens next in TFZ. But the stress is high in this area of Iceland according to GPS measurements. As some of the fault lines in TFZ are locked in place, while the whole system remains on the move otherwise. This builds up stress levels on the fault lines that are locked and unable to move in accordance with other tectonic movements in the area. This lock is then released in large earthquakes in TFZ that happen once to twice a century in this area. Now it is possible that it is time for new large earthquake in this area. But when is impossible to know for sure at the moment.

Some rock collapse has happened following the Mw5.6 earthquake on TFZ. This has been reported in local news media in Skagafjörður.

Icelandic news of rock collapse

Hrun í kjölfar skjálfta (Icelandic, pictures) Note that second picture is from the year 2006. The newest picture is the smaller frame and shows two blocks of rock that is at least 80 to 200 tons that broke loose in the largest earthquake on 20.10.2012.

Update 1: Icelandic Meteorological Office has issued this information this earthquake swarm. It can be found here on there web page.

Blog post updated at 20:59 UTC on 26.10.2012

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Uncertainty level is declared in north Iceland due to risk of large earthquake from TFZ

Uncertainty level has been declared in north Iceland due to risk of large earthquake taking place in TFZ. This is done after consulting scientists that have been monitoring this area for the past few days since the earthquake swarm started in TFZ. It is still impossible to know when a large earthquake might take place in TFZ. But the earthquake swarm is still ongoing with little change.

The Civil Protection of Iceland announcement

Óvissustigi almannavarna lýst yfir vegna jarðskjálftahrinu úti fyrir Norðurlandi (Icelandic)

Icelandic news about this

Óvissustigi almannavarna lýst yfir (Rúv.is)
Lýsa yfir óvissustigi almannavarna vegna jarðskjálftahrinu (mbl.is)